JPH09233270A - Power supply for driving image scanner of printer and printer provided with power supply for driving image scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost by dropping a voltage of a power supply for driving a recording head and using the resulting power supply for a power supply for an image scanner so as to eliminate the need for separate provision of a driving power supply to drive the image scanner. SOLUTION: A power supply for driving an image scanner is obtained from a drive power supply of a thermal head not always driven when the image scanner is driven. A DC-DC converter 29 connecting to the drive power supply for the recording head 5 steps down a voltage of 26-36V to drive the thermal head 5 into a voltage of 12V, which is used for the power supply to drive the image scanner. Thus, it is not required to provide a power supply of 12V especially to drive the image scanner in addition to the three power supply voltages outputted from a common power supply 30, then a complicated circuit is avoided and the cost increase is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive power supply for an image scanner of a printer including a recording head and an image scanner for reading a document image, and a printer including the drive power supply for the image scanner.

[0002]

2. Description of the Related Art Conventionally, a predetermined recording medium is sandwiched between a conveying roller and a pressure contact roller which is in pressure contact with the conveying roller, and the medium is conveyed between a platen and a thermal head, which is one type of recording head, and thereafter, The thermal head is pressed against the recording medium with a predetermined pressing force, and in this state, the carriage is moved, and while the ink ribbon of the ribbon cassette is being wound, the heat generated on the thermal head based on the desired print signal. A thermal transfer printer is often used which conducts desired printing on the recording medium by energizing the element and heating the heating element to melt the ink of the ink ribbon and transfer it to the paper.

In recent years, an image scanner of a document is read by attaching an image scanner to the carriage and moving the carriage while the predetermined document is being conveyed between the carriage and the platen to cause the image scanner to scan. A thermal transfer printer has been proposed which prints on a predetermined recording medium based on this image data.

A printer equipped with this image scanner is formed as shown in FIG. That is, a flat platen 2 and a carriage shaft 3 parallel to the platen 2 are provided between the left and right side plates of the frame 1 of the thermal transfer printer. The carriage 4 has a carriage 4 attached to it.
A thermal head 5 is attached to the tip of the carriage 4 so that it can move toward and away from the platen 2 so as to face the platen 2. An ink ribbon (not shown) is housed on the upper surface of the carriage 4, and a ribbon cassette 6 for guiding the ink ribbon between the thermal head 5 and the platen 2 is detachably mounted. A winding bobbin 7 for winding the ink ribbon of the ribbon cassette 6 and a feeding bobbin 8 for feeding the ink ribbon are arranged on the upper surface of the carriage 4.

Further, as shown in FIGS. 5 and 6, one side (left side in the illustrated example) of the carriage 4 has an image having a rectangular box-shaped case 9a made of synthetic resin such as plastic. A scanner 9 is provided, and as shown in FIG. 7, the opening 1 is formed on the surface of the case 9a of the image scanner 9 facing the platen 2.
0 is formed. Also, inside the case 9 a of the image scanner 9 and on both sides of the opening 10,
Two light emitting members 11, 11 including a lamp and the like are arranged so as to be directed to the opening portion 10, and the light emitting member 11 is provided inside the case 9 a of the image scanner 9.
An image sensor unit 12 that receives the reflected light of the light emitted from the document to read a predetermined image is provided.

The carriage 4 is connected to a carriage drive belt 16 which is wrapped around a drive pulley 14 and a driven pulley 15 disposed near the lower side of the left and right plates of the frame 1 so as to run freely. . The drive pulley 14 is connected to the output shaft of the carriage drive motor 13,
The carriage 4 is reciprocally moved together with the carriage driving belt 16 by the carriage driving motor 13 rotating in the forward and reverse directions.

Further, the frame 1 of the thermal transfer printer
As shown in FIG. 8, a roller shaft 17 is provided between the left and right side plates of the roller shaft 17. The roller shaft 17 is provided with a carrying roller 18 for carrying a document to be read and a predetermined recording medium at a predetermined speed. It is arranged so as to rotate integrally with 17. Also, the roller shaft 17
A conveyance motor (not shown) for rotating and driving the roller shaft 17 is disposed near the roller shaft 17 and is connected to the roller shaft 17 via a gear group. Below the transport roller 18, a plurality of pressure rollers 19 that are pressed against the transport roller 18 are rotatably disposed. Further, a sheet feeding device (not shown) is arranged behind the frame 1, and the sheet feeding device accommodates a recording medium such as a predetermined document or a normal printing sheet. It is done like this.
Then, by rotating the conveying roller 18, the original and the recording medium supplied from the paper feeding device between the conveying roller 18 and the pressure contact roller 19 are conveyed between the thermal head 5 and the platen 2. It is designed to do. Further, above the platen 2, a paper discharge roller 20 for guiding the recording medium after printing is arranged.

[0008]

However, in the printer described above, 26 to 36 V is used to drive the thermal head 5, 24 V is used to drive the drive motor 13 of the carriage 4 or the transport motor, A DC power supply of 5V is required to drive other logic circuits, and a DC power supply of 12V is required to drive the newly installed image scanner 9, which complicates electrical connection and reduces costs. It has a problem that it causes up.

Further, the lamp used as the heat generating member 11 of the image scanner 9 sometimes deforms the case 9a of the image scanner 9 due to the temperature rise due to the heat generated when the image scanner 9 is driven.

For example, when the image scanner 9 reads data, the computer that processes the read data is busy with other processing, and therefore when the read data cannot be transmitted, the printer has not processed the read data. One of them is configured to be in a standby state with the lamp used as the heat generating member 11 of the image scanner 9 kept lit. However, if this standby state lasts for a long time, the above problems may occur. It may be possible to turn off the power to turn on the lamp when the read data cannot be sent to the printer, but once the power is turned off, it takes time to restart the lamp, which affects the life of the lamp itself. It is possible that

The present invention has been made paying attention to the fact that the image scanner is not driven when the recording head is driven, and the recording head is not driven when the image scanner is driven. An object of the present invention is to provide a drive power supply for an image scanner of a printer that can be used as a drive power supply for an image scanner by lowering the power supply voltage, and a printer that can control the output voltage of the drive power supply for the image scanner. It is a thing.

[0012]

In order to achieve the above object, a drive power source for an image scanner of a printer according to claim 1 of the present invention comprises a recording head as recording means and an image scanner as image reading means. An image scanner drive power supply for supplying the drive power to the image scanner of the installed printer, the DC-DC converter supplying the drive power to the image scanner by lowering the voltage of the recording head drive power supply. It is characterized by having.

According to the drive power source for the image scanner of the printer of the present invention, it is not necessary to separately provide a drive power source for driving the image scanner, and the thermal head is not always driven when the image scanner is driven. Since the power supply for the scanner is used, drive noise is not picked up in the read data of the image scanner, good scanning can be performed, and the voltage of the power supply supplied is higher than the required voltage. It is possible to remove the fear of heat generation.

According to a second aspect of the present invention, an image of a printer that supplies driving power to the image scanner of a printer equipped with a recording head as a recording unit and an image scanner as an image reading unit. A driving power supply for a scanner, a DC-DC converter for dropping the voltage of the driving power supply for the recording head, and the DC
A three-terminal regulator for dropping the output voltage of the DC converter and supplying it to the image scanner.

According to the driving power source for the image scanner of the printer of the present invention, in addition to the function of the driving power source for the image scanner of the printer according to claim 1, a DC-D is further provided.
Switching noise of the C converter can also be reliably removed through the three-terminal regulator.

According to a third aspect of the present invention, there is provided a printer including a driving power source for an image scanner, a recording head as a recording unit, an image scanner as an image reading unit, and a printer for supplying the driving power source to the image scanner. A drive power supply for the image scanner, a voltage detection unit for detecting the voltage of the drive power supply supplied to the image scanner, a data transmission standby time of the image data, and a count value indicating the counted data transmission standby time. And a voltage control means for controlling the voltage of the drive power supply to be supplied to the image scanner when the voltage exceeds a predetermined value, the printer according to claim 4 is characterized in that A printer, wherein the drive power source for the image scanner is the printer according to claim 1 or 2. Characterized in that it is a image scanner for driving power supply.

According to these printers, when the data transmission waiting time of the image scanner exceeds a predetermined time, the voltage of the driving power supply supplied to the image scanner is lowered, so that the heat generating member of the image scanner is The temperature rise can be reliably prevented.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows a first embodiment of a drive power source for an image scanner of a printer according to the present invention, which is mounted on the thermal transfer printer shown in FIGS. 5 to 8.

In the present embodiment, the common power source 30 which has been conventionally used is used to connect the thermal head 5 to the thermal head 26.
Direct current voltage of 36V, 24V to the carriage driving motor 13 and 5V for logic is supplied. Further, in the present embodiment, the recording head drive power source for supplying the drive voltage to the thermal head 5 is supplied with DC-DC.
Connect the converter 29 to the image scanner 9
An image scanner drive power supply for supplying a DC voltage of V is formed. The DC-DC converter 29 is formed so as to reduce the DC voltage of 26 to 36V output from the recording head drive power source and output it as a DC voltage of 12V. In addition, by providing a strong filter on the output side of the DC-DC converter 29, the DC
-It is preferable to prevent the switching operation of the DC converter 29 from being picked up as noise.

Here, the reason why the carriage driving power source of the common power source 30 is not used as a power source for driving the image scanner 9 is that the carriage 4 needs to be driven also when driving the image scanner 9. Therefore, using the carriage driving power source as the driving power source for the image scanner 9 may cause driving noise of the carriage driving motor 13 to be picked up by the reading data of the image scanner 9, and thus good data may not be obtained. Is large.

FIG. 2 shows a schematic structure of a control system for operating the printer.

The thermal transfer printer is controlled by a CPU 21, and the CPU 21 stores recording conditions suitable for each type of recording medium used.
An OM 22 and a RAM 23 for storing various data are provided.

Recording data is sent to the CPU 21 from an input device such as a computer via an interface. Also, the image data read by the image scanner 9 is once sent to a computer or the like, and the CPU 21
Will be sent to you via the interface.

Further, the CPU 21 sends recording pattern information to the thermal head drive circuit 24, and the thermal head 5 is driven according to the recording information. Further, from the CPU 21, the image scanner drive circuit 2
5, a drive circuit 26 of a head up / down mechanism that presses and separates the thermal head 5 from a recording medium, a carriage drive circuit 27 that controls the movement of the carriage 4, and a conveyance that controls a conveyance motor for conveying the recording medium. Control signals are respectively sent to the motor control circuit 28 and the like.

Next, the operation of this embodiment will be described together with the printing operation.

First, since the original is read by the image scanner 9 of the thermal transfer printer, the original is stored in the paper feeding device.

Then, by sending a control signal from the CPU 21 to the carry motor drive circuit 28, the carry motor is driven to drive the carry roller 18 to rotate, so that the carry roller 18 and the press roller 19 from the paper feeding device are driven.
The original supplied between the sheet and the sheet is conveyed between the thermal head 5 and the platen 2.

When it is confirmed that the original has been correctly conveyed, the image scanner 9 is driven to shift to the original reading operation.

That is, while the carriage drive motor 13 is driven by the control signal from the CPU 21 to move the carriage 4 to cause the image scanner 9 to scan the document in the lateral direction (hereinafter, referred to as scanning direction), each light emitting member. 1
The document is irradiated with light from 1, and the reflected light from the document is received by the detection element of the image sensor unit 12 to read the image data in the scanning direction of the document, and C
The image data is stored in the RAM 23 of the PU 21 and is transmitted to the computer via the interface.

At that time, the power source for driving the image scanner 9 is the DC-DC converter 29 connected to the driving power source of the thermal head 5 which is not always driven when the image scanner 9 is driven. 26-36V power supply supplied for driving the image scanner 9 is lowered to 12V and used as a power supply for driving the image scanner 9.

By doing so, the common power source 3 described above is used.
In addition to the three power supply voltages output from 0, it is not necessary to additionally provide a 12V power supply for driving the image scanner 9, so that it is possible to suppress the cost increase without complicating the circuit.

After that, the transport roller 18 is driven to transport the document by a predetermined amount in the direction intersecting with the scanning direction, the image data of the document is read by the image scanner 9 while moving the carriage 4 again, and the RAM 23 is read again.
To memorize.

By repeating such operations, all the image data of the entire original is read and stored in the RAM 23 as a storage device, transmitted to the computer through the interface, and the original is ejected to eject the original. The image data reading operation is completed.

Next, the print medium is set in the paper feeding device, and the carry motor is driven by the control signal from the CPU 21 to rotate and carry the carry roller 18,
The print medium supplied from the sheet feeding device between the conveying roller 18 and the pressure contact roller 19 is conveyed between the thermal head 5 and the platen 2.

Thereafter, while the thermal head 5 is in pressure contact with the platen 2, the carriage driving motor 13 is driven to move the carriage 4, and the winding bobbin 7 is rotationally driven to wind the ink ribbon. By selectively heating the heating elements of the thermal head 5 based on the image data of the document stored in the RAM 23, desired printing is performed on a predetermined print medium according to the recording conditions stored in the ROM 22. .

FIG. 3 shows a second embodiment of the drive power source for the image scanner of the printer of the present invention. In the present embodiment, the output side of the DC-DC converter 29 of the first embodiment described above is shown. , 3 terminal regulator 31
It is configured to be connected. Only the points different from the first embodiment described above will be described below.

In the present embodiment, the power source for driving the image scanner 9 is a DC-DC converter 29 connected to the driving power source of the thermal head 5 which is not always driven when the image scanner 9 is driven.
26 supplied to drive the thermal head 5
The power supply of ~ 36V is once lowered to about 15V. Then, the dropped voltage is further applied to the three-terminal regulator 3
1 to lower the DC voltage to 12V, and
The switching noise of the C-DC converter 29 is surely removed, and it is used as a power supply for driving the image scanner 9.

The three-terminal regulator 31 is supplied with 26 to 26 for driving the thermal head 5.
It is impossible to use a 36V power supply to directly drop it to 12V because it generates heat, but a product that can withstand a voltage of 5V or less and is inexpensive is commercially available.
It is easy to apply and is safe to use.

As described above, according to this embodiment, it is not necessary to separately provide a 12V power source for driving the image scanner 9 in addition to the three power source voltages output from the common power source 30 described above. The cost can be suppressed without complicating the circuit, and the DC
-The switching noise of the DC converter 29 can be reliably removed.

FIG. 4 shows an embodiment of a printer equipped with a drive power source for an image scanner of the present invention,
This printer has the DC-DC converter 2 on the output side of the DC-DC converter 29 of the first embodiment.
A voltage detection unit 32 for detecting the voltage of the driving power source for the image scanner, which is output from 9, is provided.

Further, in the printer equipped with the drive power source for the image scanner of the present embodiment, the data transmission waiting time of the image data is counted, and this count value T1
Is greater than a predetermined value T2, the image scanner 9
A voltage control means 33 for transmitting a control signal for lowering the voltage of the driving power supply supplied to the voltage detection portion 32 is provided, and the voltage control means 33 is provided for the CPU 21.
Is also connected.

Next, the operation of this embodiment will be described. The description of the same parts as those in the first embodiment will be omitted.

In the present embodiment, the power source for driving the image scanner 9 is the thermal power supplied from the DC-DC converter 29 connected to the driving power source of the thermal head 5 which is not always driven when the image scanner 9 is driven. 26 to be supplied for driving the head 5
A 36V power source is dropped to 12V and used as a power source for driving the image scanner 9.

Then, the image data read by driving the image scanner 9 is processed by RA of the CPU 21.
The image data is stored in M23, and this image data is transmitted to the computer through the interface.

At this time, when the computer cannot process the read image data because the computer is busy due to other information processing or the like, each light emitting member 11 is made to stand by in a light emitting state.

Here, the voltage control means 33 counts the waiting time of the image scanner 9 from the time when the computer cannot be connected to the computer and the read image data cannot be transmitted due to the reason of the computer, and the like. When the count value T1 exceeds the predetermined value T2, a control signal for controlling the voltage of the driving power supply supplied to the image scanner 9 to be reduced is transmitted to the voltage detection unit 32. It goes without saying that the predetermined value T2 is stored in the ROM 22 of the CPU 21 in advance.

Upon receiving the control signal, the voltage detection section 32 switches its voltage detection circuit so as to reduce the voltage of the driving power supply supplied from the DC-DC converter 29 to the image scanner 9 and output it. Control.

Then, when connection with a computer becomes possible and the read image data is transmitted, the voltage detecting circuit is set again so that the power supply for driving the image scanner 9 is set to 12V during normal driving. To switch.

For example, in the present embodiment, the DC
The -DC converter 29 causes the power supply of 26 to 36 V supplied to drive the thermal head 5 to drop to 12 V at the time of driving the normal image scanner, but by configuring as described above, When the standby state for data transmission continues, the power supply for driving the image scanner 9 can be further lowered in voltage to 6V which is about half that in the normal driving and can be supplied. Therefore, it is possible to prevent the temperature of the heat generating member of the image scanner from rising while waiting for the transmission of the image data, and further to prevent the case of the image scanner from being deformed due to the heat generation.

The present invention is not limited to the above-mentioned three embodiments, and various modifications can be made if necessary. For example, the above voltage values are
It is changed according to the function, and the voltage value dropped by the DC-DC converter is also the same. Also, as the three-terminal regulator, an appropriate one may be used according to the voltage value to be dropped.

Furthermore, in each of the above-described embodiments, the case where the thermal transfer printer is used has been described, but any serial type dot printer may be used, and for example, the same can be applied to an ink jet type printer, a wire dot type printer and the like. it can.

[0053]

As described above, since the drive power supply for the image scanner of the printer of the present invention is constructed and operates, the drive power supply for the recording head is dropped in voltage and used as the drive power supply for the image scanner. It is possible,
Since it is not necessary to provide a 12V power source for driving the image scanner, it is possible to suppress the cost increase without complicating the circuit, and it is possible to perform a good reading of the image scanner and the image data. Is suppressed, heat generation is suppressed when the printer cannot be transmitted to the printer, and the durability of the printer itself can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of a drive power source for an image scanner of a printer of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a control system for driving the printer.

FIG. 3 is a block diagram showing a second embodiment of the drive power source for the image scanner of the printer of the invention.

FIG. 4 is a block diagram showing an embodiment of a printer equipped with a drive power source for an image scanner of the printer of the present invention.

FIG. 5 is a plan view showing an example of a printer equipped with an image scanner of a conventional printer.

6 is a plan view of a carriage portion of the printer of FIG.

7 is a plan view of an image scanner portion of the printer of FIG.

8 is a left side view of the printer of FIG.

[Explanation of symbols]

 5 Thermal Head 9 Image Scanner 29 DC-DC Converter 30 Common Power Supply 31 Three-Terminal Regulator 32 Voltage Detection Section 33 Voltage Control Means

Claims (4)

[Claims] 1. A drive power source for an image scanner of a printer, which supplies drive power to the image scanner of a printer equipped with a recording head as recording means and an image scanner as image reading means, A drive power supply for an image scanner of a printer, comprising a DC-DC converter for lowering the voltage of the printhead drive power supply and supplying the same to the image scanner. 2. A drive power supply for an image scanner of a printer, which supplies drive power to the image scanner of a printer equipped with a recording head as recording means and an image scanner as image reading means, DC-DC that drops the voltage of the drive power source for the recording head
An image scanner drive power supply comprising a converter and a three-terminal regulator for dropping the output voltage of the DC-DC converter and supplying the voltage to the image scanner. 3. A recording head as recording means, an image scanner as image reading means, an image scanner drive power source for supplying a drive power source to the image scanner, and a drive power source voltage to be supplied to the image scanner. And a voltage detection unit for detecting the data transmission waiting time of the image data, and the voltage of the driving power supply supplied to the image scanner when the count value indicating the counted data transmission waiting time exceeds a predetermined value. And a voltage control means for controlling so as to reduce the voltage. A printer provided with a drive power supply for an image scanner. 4. The printer according to claim 3, wherein the drive power supply for the image scanner is the drive power supply for the image scanner according to claim 1.